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Biomass straw fuel has the advantage of low-carbon sustainability, and therefore, it has been widely used in recent years in coupled blending combustion with coal-fired utility boilers for power generation. At present, the drag force FD, the lift force FL, and the torque T evaluation model are very limited. In this study, within a wide range of Reynolds numbers (10 ≤ Re ≤ 2000) and incident angles (0° ≤ θ ≤ 90°), the computational fluid dynamics open source code OpenFOAM-body-fitted mesh method is used to carry out the direct numerical simulation of the flow characteristics of large cylindrical biomass particles with a high aspect ratio of L/D = 9:1. The results show that (1) the projected area of the cylinder begins to decrease after reaching the maximum at θ = 15°, while the change in the incident angle causes the formation of a smaller recirculation zone on the leeward side of the structure, and the effect of the pressure difference on the drag coefficient (CD) is reduced. (2) The lift coefficient (CL) displays a parabolic symmetric distribution when θ = 45°, and then the distribution becomes asymmetrical when Re > 100. The torque coefficient (CT) exhibits a similar trend. (3) Based on the simulation data and the literature data, new models for CD, CL, and CT for cylinders with L/D = 9:1, 10 ≤ Re ≤ 2000 and 0° ≤ θ ≤ 90° are obtained, and the mean square errors are 2.4 × 10−2, 1.4 × 10−2, and 6.4 × 10−2, respectively. This new model can improve the accuracy and adaptability of the universal model of gas–solid dynamics for biomass particles. [ABSTRACT FROM AUTHOR]

Cofiring of coal slime in existing utility boilers is a promising approach to the disposal of coal slime. However, reports about cofiring coal slime with anthracite in the down-fired utility boiler are still few. This work presents a comprehensive study on the combustion characteristics, slagging potential, and NOx emissions of cofiring coal slime and anthracite through lab-scale experiments, numerical simulations, and full-scale industrial measurements in a 600MW down-fired utility boiler. The lab-scale experiments show combustion interactions between anthracite and coal slime, which have both a promotive effect on the ignition of anthracite and inhibitive effect on the combustion and burnout of anthracite. Especially, the inhibitive effect is greater than the promotive effect when the blending ratio of coal slime is above 5%. The addition of coal slime can effectively improve the ash fusion temperature of blended samples. In addition, simulations and full-scale industrial measurements of anthracite cofiring with coal slime are performed in a down-fired utility boiler. The results show that as the blending ratio of coal slime increases, the carbon content in fly ash increases and the boiler efficiency and NOx emissions decrease. A 5% ratio is validated to be a reasonable cofiring ratio of coal slime in the actual operation without no slagging phenomenon. These results provide more insights into the cofiring behavior of coal slime and anthracite and guide the application of blending coal slime in a down-fired boiler. [ABSTRACT FROM AUTHOR]

• Food-processing sludge with extremely high moisture is treated by smouldering. • Sand: Food-processing sludge: Sawdust = 25:5:1 may be a reasonable mixing ratio. • Continuous self-sustaining smoldering is volumetrically scaled up to the pilot-scale. • O 2 , CO, NO x , SO 2 , VOC, and dioxin concentrations of flue gas are measured. • Heavy metal element is low in ash, good self-healing of smouldering is validated. Although smouldering of solid waste with high moisture has shown strong promise in laboratory studies, there are fewer reports about the larger-scale device and continuous operation. This work studies a self-sustaining smouldering treatment of food-processing sludge (FPS) with extremely high moisture (over 85 %) in laboratory- and pilot-scale devices. Results from laboratory-scale experiments show that adding auxiliary fuel is necessary to maintain FPS self-sustaining smouldering, Sand: FPS: Sawdust = 25:5:1 is a reasonable mixing ratio. Then, the self-sustaining smouldering is volumetrically scaled up to the pilot-scale. The smouldering asynchrony in the feedstock is observed due to the non-uniform air flux. Compared to the laboratory-scale, the pilot-scale device presents a similar temperature level but a higher smouldering velocity. Furthermore, a continuous process in the pilot-scale device is successfully performed, and the flue gas concentrations are measured: 15.0 ∼ 16.5 % for O 2 , 4000 ∼ 5500 ppm for CO, 155 ∼ 195 ppm for NO x , 210 ∼ 250 ppm for VOC s , 55 ∼ 70 ppm for SO 2 , 0.0138 ∼ 0.0317 ngTEQ/m3 (at 11 % O 2) for dioxin. These studied results can provide useful information for continuous, low-energy solid waste treatment. [ABSTRACT FROM AUTHOR]

Based on the pseudo-steady-state approach, the combustion effect of high-reactivity char (i.e., HR-char) on low-reactivity char (i.e., LR-char) is investigated numerically in a hot O 2 /CO 2 atmosphere under two arrangements (LR-LR case : the upstream and downstream particles are LR-char, HR-LR case : the upstream particle is HR-char and the downstream particle is LR-char). This paper is aimed to study the influence of oxygen concentration (from 2% to 30%) and ambient temperature (1300 K, 1400 K, and 1500 K) on the combustion effect under the condition with dominated oxidation reaction and weak gasification reaction, and explain the mechanism in aspects of the temperature, specie concentration, and reaction rate. The numerical results are carefully validated against experimental data published in the literature. The results show that under these studied ambient temperatures, the char-O 2 oxidation-reduction brings a more pronounced effect than the char-CO 2 gasification enhancement for char consumption owning to the dominant role of the char oxidation reaction. The upstream HR-char particle combustion under the HR-LR case produces a higher temperature, lower oxygen, and higher CO 2 atmosphere ahead of the downstream char than under the LR-LR case, which significantly inhibits the downstream LR-char particle combustion. In addition, lower oxygen concentration or higher ambient temperature decreases the difference in temperature, oxygen, and CO 2 between the HR-LR and LR-LR cases ahead of the downstream char, resulting in the lower difference in the downstream LR-char oxidation consumption rate between the HR-LR and LR-LR case. Consequently, the weaker combustion inhibitive effect of the high-reactivity char on the low-reactivity char is observed. The findings shed light on the interaction effects observed during blended coal combustion in O 2 /CO 2 mixtures. • Combustion effect of high-reactivity char on low-reactivity char is investigated. • Effect mechanism is studied with spatially and chemically resolved simulations. • Lower oxygen or higher ambient temperature corresponds to weaker combustion effect. [ABSTRACT FROM AUTHOR]

Smouldering is a novel low-energy, low-cost and high-effective technology for the disposal of high-moisture wastes. Most of the existing reports focus on the lab-scale studies and non-continuous operation, but the study about the large-scale device and continuous process is lacking. This work scales up the self-sustained smouldering from the lab-scaled device to the pilot-scale device for treating the printing and dyeing sludge (PDS) with high moisture (over 60%) under continuous operation. Firstly, the lab-scale smouldering experiments with different sand/PDS mixing ratios are performed, and the 4.5/1 mixing ratio is selected as a suitable mixing ratio. Then, the pilot-scale smouldering experiments are carried out and the influence of the discharging residual interval (50s, 35s, 20s) on the reaction stability is tested under continuous operation. Results indicate that the 35s for discharging residual interval may be suitable to maintain the high-temperature region at a relatively stable location under the studied operating condition. The flue gas concentrations are relatively stable during discharging residual, and the main component concentrations are 17.0–17.8% for O 2 , 2600∼3000 ppm for CO, 20∼35 ppm for VOCs, and 60∼80 ppm for NO x , 0.0415–0.0836ngTEQ/m3 for dioxin, respectively. The research in this study can give helpful information for the application of the continuous smouldering treatment in the future. [Display omitted] • Smouldering is scaled up from lab-scaled to pilot-scale for treating PDS. • Continuous operation is successfully performed in pilot-scale device. • Effect of discharging residual interval on smouldering is tested and 35s is suitable. [ABSTRACT FROM AUTHOR]

Stable flame is still one of the challenging issues in the micro-combustors. Besides, the premixed flame may flash back under the large equivalence ratio, and the non-premixed combustion is an effective way to avoid the flame flash-back issue. In this work, a novel non-premixed CH 4 /air micro-combustor with the flame holder, the backward-facing steps and the separated preheating channels is developed to avoid the flame flash-back issue and extend the flame blow-off limits. This paper investigates the influence of two different CH 4 /air injection locations on the flame blow-off limits numerically and profoundly reveals the mechanisms in this micro-combustor. Results show that this novel configuration can considerably anchor the flame without the flame flash-back issue and significantly extend flammability owning to the flow & heat recirculations. Compared with the "Air (out) /CH 4(in) " injection location, the "Air (in) /CH 4(out) " injection location exhibits a comparatively larger size of recirculation, causing a more vital anchorage ability. In addition, after the preheating in the preheating channels, the CH 4 /air mixture of the "Air (in) /CH 4(out) " injection location presents a higher temperature level than that of the "Air (out) /CH 4(in) " injection location. Consequently, compared to the "Air (out) /CH 4(in) " injection location, the larger blow-off limits are attained for the "Air (in) /CH 4(out) " injection location. These results provide new insights into the stable non-premixed flame and give valuable guidance for designing the similar non-premixed micro-combustor. [Display omitted] • A novel CH 4 /air non-premixed micro-combustor is developed. • This novel configuration can anchor the flame without the flame flash-back issue. • Influence of CH 4 /air injection locations on flame blow-off limits is studied. • "Air (in) /CH 4(out) " presents larger recirculation & better heat recirculation. • "Air (in) /CH 4(out) " attains larger blow-off limits than "Air (out) /CH 4(in) ". [ABSTRACT FROM AUTHOR]

The combustion interactions during blended coal combustion affect their combustion characteristics, and the combustion interactions under air–fuel conditions have been well studied. However, oxy–fuel combustion considerably differs from air–fuel firing. Significantly, the char–CO2 gasification reaction under oxy–fuel and high-temperature conditions substantially affects the combustion behaviors, which may influence the combustion interactions. This paper is to study the effect of the char oxidation and gasification reaction competition on comprehensive interactions in O2/CO2 mixture. The results show that under high-temperature and low-oxygen (O2<4%) conditions, an intense gasification reaction is observed. The competition between the char–CO2 gasification and char–O2 oxidation reactions influences the comprehensive interactions during blended chars combustion. As the char–O2 oxidation reaction is strengthened and the char–CO2 gasification reaction is weakened, the comprehensive interactions during blended chars combustion gradually decrease. Moreover, under the competition between the char–CO2 gasification and char–O2 oxidation reactions, only enhancing the char–CO2 gasification reaction or enhancing the char–O2 oxidation reaction weakens the comprehensive interactions. The weaker comprehensive interactions result in the smaller nonadditive behavior of the comprehensive combustion index. The findings shed light on the interaction effects observed during blended chars combustion, which can provide useful information to improve the combustion behaviors of the blended coals in oxy–fuel conditions. [ABSTRACT FROM AUTHOR]

A novel Swiss-roll micro-combustor with double combustion chambers is proposed to improve flame stability and extend blow-off limits. This study is aimed to numerically investigate the effect of solid material (i. e., SiC, stainless steel and copper) on premixed CH 4 /air flame blow-off limit and reveal the flame stability mechanism. The simulated results show that this developed novel Swiss-roll micro-combustor not only can significantly anchor the flame owing to the flow recirculation behind the flame holders and the backward-facing steps, but also can further extend CH 4 blow-off limits owing to heat recirculation in the long Swiss-roll preheating channels. The three solid material micro-combustors present the relatively slight difference in the recirculation-zone size but the remarkably difference in heat recirculation and heat loss. Good heat recirculation and low heat loss rate are the dominant reason that is responsible for the differences of the blow-off limits in this micro-combustor. The stainless steel micro-combustor achieves the highest blow-off limits while the copper micro-combustor achieves the lowest blow-off limit. These deep insights can give some useful information to design a similar Swiss-roll micro-combustor. [Display omitted] • A novel Swiss-roll micro-combustor with double combustion chambers is developed. • Effect of solid material on blow-off limit is investigated numerically. • High blow-off limits with good flame anchorage ability are observed. • Good heat recirculation and low heat loss rate affect the blow-off limit. • The stainless steel micro-combustor achieves the highest blow-off limit. [ABSTRACT FROM AUTHOR]

• Effects of SOFA angles on combustion, NO x and steam parameters are evaluated. • A SOFA angle of 30° is advisable for the novel combustion system. • Significant NO x reduction are achieved while limiting the carbon in the fly ash. A novel combustion system, consisting of moving fuel-lean nozzles from the arches to the front/rear walls, rearranging staged air, and introducing separated over-fire air (SOFA), has been proposed and successfully applied in a 600 MW e Foster Wheeler down-fired boilers to reduce high NO x emissions while limiting the carbon content in the fly ash. This study comprehensively evaluates the effect of SOFA angles on flow, combustion characteristics and NO x emissions for the novel combustion system by numerical simulation and in-situ experiment. The numerical simulation shows in acceptable consistence with the in-situ experiment. The simulated results show that significant NO x reduction is obtained for all five SOFA angles compared to the original combustion system. O 2 and CO concentrations at the furnace outlet, as well as the carbon content in the fly ash decrease significantly with increasing SOFA angle from 0° to 40°. NO x emissions increase slightly and the average temperature at the re-heater entrance changes slightly with the increase of SOFA angle from 0° to 30°. However, with further increasing SOFA angle from 30° to 40°, NO x emissions increase substantially due to the smaller reducing region below the SOFA and the average temperature at the re-heater entrance falls significantly. Taking combustion, NO x and steam parameters into account, a SOFA angle of 30° is advisable. The actual industrial measurements also show that the steam can achieve the designed values when the SOFA angle is set at 30° instead of 40°. Significant NO x reduction (over 50 %) and good performance are attained after adopting the novel combustion technology of 30 °SOFA angle. [ABSTRACT FROM AUTHOR]

An extended theoretical model based on a two-scale coupled momentum balance method is proposed to estimate aerodynamic effects of wind turbine towers on the performance of both ideal (infinitely large) and more realistic (large but finite-size) wind farms. A key implication of the extended model is that a normalized support-structure drag, A S / A × C D * , where A and A S are the rotor swept area and support-structure frontal projected area, respectively, and C D * is an effective support-structure drag coefficient, may play an important role in the design of future large wind farms. For the infinitely large case, the theoretical model shows that the optimal turbine spacing should increase with the value of A S / A × C D * , whereas for the large finite case, this also depends on an additional parameter describing the response characteristics of the atmospheric boundary layer to the total farm drag. To validate the theoretical model for the infinitely large case, Wall-Modeled Large-Eddy Simulations of a periodic array of actuator disks with and without support structures are conducted. The results show a reasonably good agreement (within 10% in the prediction of power) with the theoretical model. [ABSTRACT FROM AUTHOR]

During the pneumatic conveyance of biomass in a coal-fired power station boiler, biomass particles have cylindrical shapes with different aspect ratios. They move through the fluid at any angle and rotate strongly. However, highly accurate and general models of the drag, lift, and torque coefficients (CD, CL, and CT) for biomass particles in a wide range of aspect ratios, especially the CT model and the high aspect ratios, are currently lacking. This paper presents detailed direct numerical simulations of the flow around cylindrical cylinders with varying aspect ratios (6 ≤ AR ≤ 22), Reynolds numbers (100 ≤ Re ≤ 2000), and angles of incidence (0° ≤ θ ≤ 90°). The simulation was conducted using the OpenFOAM solver with the body-fitted mesh method. The flow characteristics and force coefficients of cylindrical particles with different AR were systematically analyzed. New functional correlations between CD, CL, and CT and AR, Re, and θ values were established. The mean squared errors for CD, CL, and CT were 8.8 × 10–2, 2.4 × 10–2, and 4.7 × 10–2, with average relative errors of 5.8%, 3.5%, and 8.17%, respectively. A comparison of the results with other experimental and simulation data in previous literatures showed that the new CD and CL models have considerable higher predictive ability. The generality of the new CD model expanding to low ARs of 1.5 and 3 is verified finally. The new force and torque models are expected to improve the accuracy of Eulerian–Lagrangian simulations of various cylindrical particle-laden flows in the utility of biomass energy. [ABSTRACT FROM AUTHOR]

Co-incineration of sludge in the existing coal-fired utility boilers is a promising sludge disposal approach, but study on the combustion characteristics and the economic impacts of co-firing sludge in full-scale utility boilers is in absence. In this study, a series of full-scale field experiments and numerical experiments were conducted to study the coal-sludge co-combustion characteristic in a 100 MW coal-fired utility boiler. The effects of sludge blending ratio and moisture content in sludge are concerned. Subsequently, the economic impacts of co-firing sludge is presented. The results demonstrate that the combustion characteristics is acceptable when co-firing 10% sludge. The ignition property and the flame stability are significantly affected when the mass content of co-fired sludge is over 10%. Decreasing the moisture content in sludge is beneficial to the combustion characteristics but the improvements are limited. Co-firing sludge is profitable for power plants as the savings from coal and sludge disposal allowance is quite substantial. Considering both the combustion characteristics and the economic impacts, co-firing 10% sludge with moisture content ranging from 40% to 56% is optimal. The annual profit from co-firing sludge can reach 4.2 million to 5.5 million Chinese yuan (CNY), which is remarkable for the power plant. [ABSTRACT FROM AUTHOR]

A novel combustion system has been applied to a 600 MW e down-fired boiler to reduce NO x emissions without producing an obvious increase in the carbon content of fly ash. The system mainly includes moving fuel-lean nozzles from the arches to the front/rear walls, and re-arranging the staged air, as well as introducing separated-over-fire air (SOFA). This paper evaluates the effects of the SOFA locations (on the arches, on the throat, and on the upper furnace) on the combustion and NO x emissions characteristics using simulations. The numerical results are in good agreement with the measured results. Compared to the original combustion system, significant NO x reduction (approximately 50%) is found for all three SOFA location settings. Taking economic efficiency and NO x emissions into account, the SOFA on the upper furnace is adopted in the actual modification, and no negative effects are observed. [ABSTRACT FROM AUTHOR]

Abstract: SrAl2O4:Eu phosphors with various doping concentrations were synthesized via a urea assisted solution-combustion method in a reducing atmosphere without any post-annealing process. The phosphors were characterized by X-ray powder diffraction (XRD), field emission scanning electron microscopy (SEM), photoluminescence (PL), X-ray excited luminescence (XEL), and X-ray photoelectron spectroscopy (XPS). The XRD results show that the samples exhibit a monoclinic phase in crystal structure. The PL measurements show that the intensity of luminescence emission from divalent Eu2+ ions is increased with increasing europium concentration up to a maximum of 2.5mol%, then decreases at higher concentration due to the concentration quenching effect. The emission from trivalent Eu3+ ions occurs when the doping concentration is higher than 12.5mol%. The XPS measurements also confirm the trends of Eu2+ and Eu3+ with changes in concentration. The results indicate that the luminescence color components of the phosphors can be adjusted by the doping concentration; this is a very important result for practical applications. [Copyright &y& Elsevier]

Abstract: Ultraweak biophoton emission of cutting-injured sweet potato is enhanced by the incubation with Ag nanoparticles in a nonlinear way. The late peak of the emission after the cutting injury is amplified as much as 15 times, while only little amplification was identified for the emission measured immediately after the cutting. The effect requires the presence of nutritive media to support the active metabolic processes and is also affected by the timing of the addition of the Ag nanoparticles. Proposed mechanisms of reactive oxygen species generation and energy resonance transfer are discussed. [Copyright &y& Elsevier]

Coal combustion is the major contributor to global toxic selenium (Se) emissions. Inorganic elements in coals significantly affect Se partitioning during combustion. This work confirmed that the calcium (Ca) in ash had a stronger relationship with Se retention at 1300 °C than other major elements. Ca oxide chemically reacted with gaseous Se, and its sintering densification slightly affected Se adsorption capacities (44.45 −1840.71→35.17 −1540.15 mg/kg) at 300 − 1300 °C. Therefore, Ca in coals was identified as having potential for hindering gaseous Se emissions, and coals with increased Ca contents (2.74→5.19 wt%) were used in a 350 MW unit. The decreased Se mass distribution (3.54%→2.63%) in flue gas at air preheater inlet (320 −362 °C) confirmed the effectiveness of increased Ca content on gaseous Se emission reduction. More gaseous Se further condensed and was chemically adsorbed by fly ash when passed through an electrostatic precipitator, resulting in a significant increase in the Se content of fly ash. Additionally, the corresponding Se leaching ratio decreased from 4.88 − 35.74% to 1.87 − 26.31%, indicating enhanced stability of Se enriched in fly ash. This research confirmed the feasibility and environmental safety of sequestration of gaseous Se from flue gas to fly ash by increasing the Ca content in coals. [Display omitted] ● Se retention at 1300 °C is associated with Ca content in ash. ● Ca oxide removes more gaseous Se via chemical reaction during flue gas cooling. ● Coals with higher Ca contents will release less gaseous Se into flue gas. ● A higher Ca content in fly ash can enhance the stability of Se within. ● Electrostatic precipitator induces Se emission reduction with increased Ca content. [ABSTRACT FROM AUTHOR]

Down-fired boilers are commonly used to burn low-rank coals for power generation. However, they often have operational problems such as low char burnout and high NO x emissions. This paper comprehensively investigates how to mitigate such problems in a 300 MW e down-fired utility boiler burning a low-volatile coal by optimizing the staged-air windbox structure. First, experiments and simulations are conducted on a 1:1-scaled model of the staged-air windbox to study the cold air flow in the original and two new windbox structures for understanding the effect of different staged-air windbox structures. Then, combustion simulations are performed for the utility boiler to further study the influence of the newly designed staged-air windboxes on the boiler performance, based on which the optimization scheme of the staged-air windbox in the boiler is more reliably concluded. Finally, the utility boiler is retrofitted by using a newly designed staged-air windbox. Performance tests are made for the boiler before and after the retrofit. The new staged-air windbox is confirmed to greatly improve the performance of the utility boiler, e.g., NO x reduction by 20.7% and thermal efficiency increase by nearly 2 percentage points (from 88.76% to 90.48%) at full load. The idea of the new staged-air windbox design can be readily implemented into down-fired boilers of this kind for more efficient and environmentally friendly firing of low-rank coal for heat and power generation. • Down-fired systems commonly used to burn low-rank coal but with operation problems • Modelling and testing done on both testrig and boiler for effect of staged-air box • A simple and smart optimization of staged-air box improves downshot-fired system • At full load, NOx reduction by 21% and efficiency increase by 2 percentage points. [ABSTRACT FROM AUTHOR]

• A unique high-throughput microbial respiration activity testing apparatus designed. • Microbial respiration intensity in six common biomass fuels during storage explored. • Initial fuel moisture of 136% for peak microbial metabolic activity identified. • Ambient temperature range of 35–45 ℃ for peak microbial metabolism observed. • Novel approach to construct a predictive model for biomass self-heating proposed. As a critical renewable energy source, biomass has substantial potential for reducing carbon emissions and promoting sustainable development. However, its long-term storage in large volumes for modern bioenergy poses challenges due to inherent self-heating driven by exothermic microbial, physical and chemical processes, which can lead to spontaneous ignition and severe fire incidents. While physical and chemical aspects of self-heating in biomass piles greatly benefit from extensive research and experience borrowed from coal pile self-heating, microbial activities in biomass self-heating have received less attention. To address this knowledge gap, we conduct a series of comprehensive studies to gain a deeper understanding of microbial activities in biomass self-heating, aiming to develop a numerical model for reliably predicting biomass self-heating and minimizing fire risks in stored biomass. This paper presents the results of our experimental investigation into microbial respiration during biomass storage. Six commonly used biomass feedstocks with varying initial moisture content are subjected to different storage conditions over a seven-day testing period, during which the main metabolic byproduct (CO 2) released from microbial degradation of the biomass is continuously measured. Our findings reveal that an increase in feedstock moisture content significantly enhances microbial activity when the initial moisture content is below 136 %. However, further increases in initial moisture content do not notably enhance, and in some cases, may even weaken microbial activity. Additionally, a temperature range of 25 °C to 45 °C is identified as conducive to rapid microbial decomposition for different biomass materials, and deviation from this range results in a significant reduction in microbial activity. Furthermore, under identical temperature and initial moisture content conditions, the order of carbon dioxide evolution rate is as follows: corn stalk > soybean hull > rice straw > wheat straw > cotton stalk > pepper stalk. Our respiration intensity test results also create a fundamental experimental database for model development and validation, and contribute to the broader understanding of biomass storage and its associated challenges. [ABSTRACT FROM AUTHOR]

Grate boilers are widely applied in biomass combustion for heat and energy generation. However, grate-firing systems often suffer from low efficiency and high emission. Computational fluid dynamic (CFD) becomes increasingly popular as a flexible method to obtain the detailed combustion behaviors in the furnace, and to optimize the performance of existing grate boilers. This paper presents efforts toward a reliable baseline CFD model for an industrial biomass-fired grate boiler, where the structure of the fuel-bed was sufficiently considered. The combustion performances in the furnace were investigated experimentally and numerically by coupling the fuel bed and freeboard, to clarify the impact of bed structure on the simulation accuracy. Results show that when the bed structure has been taken into account, the predictions are in better agreement with the various measurements, as the deviations between them are all within 10 %. Moreover, the flame center drops, the total heat transferred to the water-cooled walls increases, and the residence time of flue gas is greatly prolonged from 2.76 s to 3.90 s, resulting in a distinct difference of the temperature and species patterns in the freeboard. The simulations will provide valuable theoretical guidance for the accurate modeling of grate-fired boiler. [Display omitted] • A baseline model is proposed for accurate modeling of biomass-fired grate boiler. • Effect of fuel-bed structure on the simulation of grate boiler is clarified in detail. • Bed structure greatly affects the predicted temperature and species patterns. • Flue gas residence time and heat transfer are also highly impacted by bed structure. [ABSTRACT FROM AUTHOR]

To reduce heavy metals (HMs) contamination from tannery sludge, this study investigated the migration behaviour of arsenic (As) and chromium (Cr) at 700–900 °C using CO 2 gasification. The HMs enrichment results showed that As contents of ash decreased (6.42→1.87 mg/kg) while Cr contents increased (41.40→78.24 mg/kg) over 700–900 °C. More Si-O bonds and fewer Ca-O bonds with increasing temperature in ash primarily determined this migration behaviour of HMs. Meanwhile, the proportions of toxic As(III) and Cr(VI) declined from 96.02% and 64.26–76.96% and 21.24%, forming As(0) and Cr(III) with less toxicity. This reduction was conducted via two pathways: (i) carbon reduced As(III)/Cr(VI) and (ii) carbon reduced Fe(II)/Fe(III) to Fe(0), then Fe(0) reduced As(III)/Cr(VI) assisted with carbon via Fe(0)→Fe(II)→Fe(III). However, free calcium ions oxidized As(0)/Cr(III) to As(III)/Cr(VI) at 700 ○C. At higher temperatures, silicate glass conversion of ash immobilized free calcium ions and barely oxidized HMs. Furthermore, this study identified the positive effect of increasing temperature on enhancing the stability of HMs in ash by transforming bioavailable HMs into non-bioavailable HMs, which decreased the leaching toxicity and environmental risk. Regarding HMs emissions control and cold gas efficiency, CO 2 gasification treatment of tannery sludge is most effective at 800 °C. [Display omitted] • Silicate glass transformation of ash occurred above 800 °C under CO 2 gasification. • Temperatures exceed 800 °C greatly reduced As(III)/Cr(VI) to As(0)/Cr(III). • Over 88.16% and 87.63% of As and Cr in ash were non-bioavailable above 800 °C. • Environmental risk of ash was at low risk at 700–900 ○C under CO 2 gasification. • 800 °C was more suitable for tannery sludge disposal under CO 2 gasification. [ABSTRACT FROM AUTHOR]

Biomass is essential for modern bioenergy applications, but long-term storage of large volumes of it can pose challenges to plant safety due to the intrinsic self-heating characteristics of biomass piles. In recent years, serious fire accidents have occurred because of self-heating. However, little research has been conducted on this concern. The effects of different initial moisture contents (range of 20–95 %) on the self-heating characteristics of rice and wheat straw, which are two different agricultural biomass residues, are investigated in this study. Biomass samples with different initial moisture contents are stored in a well-insulated container, and the temperature and oxygen levels within the stored biomass samples are monitored. Based on the tests, the heat production rate, oxygen consumption rate and microorganism growth rate are derived, and the impacts of the initial moisture contents on the self-heating characteristics of the stored biomass samples are analysed. The highest temperatures in the stored rice straw and wheat straw are attained under initial moisture contents of 50 % and 20 %, respectively, while the largest heat production rates for both straw types are attained under an initial moisture content of 95 %. An increase in the initial moisture content greatly enhances the overall biological reactivity and oxygen consumption rate. The heat production and oxygen consumption levels exhibit a clear positive correlation. Under identical storage conditions, wheat straw is more susceptible to self-heating than rice straw, as shown by its higher heat generation, faster oxygen consumption, and shorter temperature peaking time. This study contributes to a quantitative understanding of the underlying processes and provides valuable experimental data for model development to guide safe biomass storage systems. • Biomass heat production increases nearly linearly with increasing moisture content. • Positive linear relationship between oxygen consumption rate and heat production. • Wheat straw exhibits higher microbial activity than rice straw at low oxygen levels. • Optimal moisture content is critical for high-temperature attainment in biomass. • Excessive biomass oxygen consumption rate restricts reaching of high temperatures. [ABSTRACT FROM AUTHOR]

With the increase in the proportion of new energy power generation in grids, there is an urgent need for the flexible operation of coal‐fired power plants. However, as the most efficient commercial coal‐fired power generation technology, the flexibility of double‐reheat ultra‐supercritical units is limited due to the steam temperature fluctuation in transient processes. To inhibit the steam temperature fluctuations, a data‐driven method, called long short‐term memory (LSTM) was introduced to model the dynamics of the steam temperatures of a 1000‐MW double‐reheat coal‐fired boiler. Moreover, an advanced controller was proposed by combining the LSTM‐based dynamic model and the model predictive control architecture. The results demonstrate that the LSTM model can be used to capture the time delay, multivariable coupling and non‐linear dynamics of the steam temperatures and the proposed controller exhibits excellent performance in steam temperature regulation. The superheated steam temperature fluctuation decreases from 15.4 to 9.8°C, the primary reheat temperature fluctuation decreases from 34.6 to 8.3°C, and the secondary reheat temperature fluctuation decreases from 41.4 to 8.8°C. The proposed method has good potential to stabilize steam temperatures during transient processes of wide‐range load cycling, and finally improves the flexibility of the double‐reheat ultra‐supercritical unit. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) is a primary malignancy of the liver and occurs predominantly in patients with underlying chronic liver disease and cirrhosis. HCC is now the third leading cause of cancer deaths worldwide, with over 500,000 people affected. However, there is no complete effective (ideal) treatment for liver cancer yet, and the new methods are expected to be discovered. Herein, for the first time, we report the anti-HCC effects of copper-cysteamine nanoparticles (Cu-Cy NPs), a new type of photosensitizers. An in vitro 3-(4,5-dimethylthiazol- 2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay shows that Cu-Cy NPs could significantly reduce the activity of HepG2 cells at a very low dose after a short time of ultraviolet radiation. In addition, we found that cell death was induced by Cu-Cy NPs, which is associated with cellular apoptosis. This implied that apoptosis might be the main mechanism of the Cu-Cy's anti-HCC activity. Furthermore, we found that Cu-Cy NPs obviously inhibited the tumor growth in vivo. More interestingly, we found that the soluble Cu-Cy NPs were able to enter exosomes which were secreted by tumor cells, and exosomes could be used to deliver Cu-Cy NPs to target tumor cells. All these observations suggest that Cu-Cy NPs have a good potential for cancer treatment. [ABSTRACT FROM AUTHOR]

For the first time, X-ray excited luminescence of Sr 2 MgSi 2 O 7 :Eu 2+ , Dy 3+ , an efficient persistent phosphor with good potential for lighting, biological imaging and photodynamic activation, is reported in this paper. A modified Sol-Gel method is used to synthesize Sr 2 MgSi 2 O 7 :Eu 2+ , Dy 3+ phosphors and their luminescence properties are highly associated with the synthesis conditions. The dependences of the X-ray excited optical luminescence and persistent luminescence of Sr 2 MgSi 2 O 7 :Eu 2+ , Dy 3+ on the reaction pH, temperature, ratio of Eu/Dy, and the calcination duration time are investigated and the association of the luminescence behaviors with the synthesis conditions is explored as a good strategy to optimize the phosphors for practical applications. [ABSTRACT FROM AUTHOR]

Abstract: Sonodynamic therapy (SDT), as a newly emerging and promising modality for cancer treatment, has been extensively investigated but with limited therapeutic outcome because of the absence of highly efficient sonosensitizer. Copper–cysteamine (Cu–Cy), as a new sensitizer, has been reported for oxidative therapy which can be activated with light, X‐ray, or microwave. Herein, for the first time, Cu–Cy nanoparticles are reported as new sonosensitizers for SDT on breast cancer treatment. Upon exposure of Cu–Cy nanoparticles to ultrasound, a large quantity of reactive oxygen species (ROS) are generated for cancer cell destruction with a high SDT efficiency to induce cell apoptosis and necrosis as observed in vitro. In vivo animal studies show a significant inhibition of tumor growth for the xenografts of 4T1 cancer cells with the combination of 0.75 mg kg−1 Cu–Cy and ultrasound. Overall, the preliminary results show that Cu–Cy nanoparticles can significantly augment the levels of ROS induced by ultrasound, demonstrating Cu–Cy is a new kind of efficient sonosensitzers for SDT applications. Such therapeutic platform by integrating a noninvasive, highly safe, deep‐penetration ultrasound modality. and quickly developed versatile nanosensitizers for tumor eradication will facilitate SDT future clinical translation. [ABSTRACT FROM AUTHOR]

Nanosonosensitization by Using Copper-Cysteamine Nanoparticles Augmented Sonodynamic Cancer Treatment GLO:OLV/01dec22:ppsc202200155-fig-0001.jpg PHOTO (COLOR): 6 The in vivo ROS generation detected through fluorescence microscopy after different treatment. gl This correction does not change any results or conclusions of the original paper. B 2018 b , I 35 i , 1700378 DOI: 10.1002/ppsc.201700378 In the original version of Figure 6, the image of US (-) Cu-Cy (+) was mistakenly misplaced. [Extracted from the article]

White light phosphors have many potential applications such as solid-state lighting, full color displays, light source for plant growth, and crop improvement. However, most of these phosphors are rare-earth-based materials which are costly and would be facing the challenge of resource issue due to the extremely low abundance of these elements on earth. A new white color composite consisted of a graphitic-phase nitrogen carbon (g-C3N4) treated with nitric acid and copper-cysteamine Cu3Cl(SR)2 is reported herein. Under a single wavelength excitation at 365 nm, these two materials show a strong blue and red luminescence, respectively. It is interesting to find that the white light emission with a quantum yield of 20% can be obtained by mixing these two self-activated luminescent materials at the weight ratio of 1:1.67. Using a 365 nm near-ultraviolet chip for excitation, the composite produces a white light-emitting diode that exhibits an excellent color rendering index of 94.3. These white-emitting materials are environment friendly, easy to synthesize, and cost-effective. More importantly, this will potentially eliminate the challenge of rare earth resources. Furthermore, a single chip is used for excitation instead of a multichip, which can greatly reduce the cost of the devices. [ABSTRACT FROM AUTHOR]

Large-scale biomass storage for modern bioenergy introduces potential safety concerns due to the intrinsic self-heating of biomass. Despite this, very limited research has been conducted in this area. This project fills a critical gap by developing a comprehensive modelling framework for self-heating in biomass piles and conducting a series of experimental studies to explore the intricate sub-processes within these piles. This paper presents only a small portion of the modelling and testing work. It successfully demonstrates the model's usefulness in predicting self-heating in coal piles, guiding safety measures for coal storage. Among various storage parameters, the pile height, particle size and ambient wind velocity have been identified as having substantial impacts on self-heating and self-ignition within the coal pile. This paper also illustrates the pronounced effects of initial biomass moisture content on microbial reactivity and oxygen consumption rate. An increase in initial moisture content significantly enhances the overall microbial reactivity and oxygen consumption rate. Wheat straw, compared to rice straw, is more prone to self-heating under identical storage conditions, as evidenced by higher heat generation, faster oxygen consumption, and a shorter time to peak temperature. Moreover, microbial activity is found to play a critical role in biomass self-heating, particularly in the temperature range of 0–75 °C, during the initial stages of heat accumulation. For the modelling discussed here, the flow within the porous pile must be considered laminar, despite the highly turbulent flow around the pile. This is based on the Reynolds number, calculated from the in-pile volume average of the velocity and the mean diameter of the fuel particles, which is significantly below the critical threshold ( R e c r = 200). The insights and sub-models to be derived from the relevant sub-processes in biomass pile can be integrated into the model framework. This integration will create a more comprehensive and robust model for predicting self-heating and self-ignition in biomass storage piles, enhancing both theoretical and practical management of these phenomena. [ABSTRACT FROM AUTHOR]

Pressurized oxy-coal combustion in conjunction with carbon capture and sequestration is a promising technique for reducing carbon emissions. Biomass is a renewable energy source of zero carbon emissions. Therefore, negative carbon emissions can be achieved with pressurized oxy-biomass combustion, which is an appealing method for carbon peaking and carbon neutralization. NOx is an acidic gas produced from combustion that has the potential to corrode pipelines, demanding strict control. However, the evolution of NOx precursors and NOx formation in pressurized oxy-biomass combustion is still unclear. In this study, the NOx emissions in pressurized oxy-combustion and nitrogen migration characteristics of biomass in a pressurized CO 2 atmosphere were studied in a pressurized fixed bed reactor. The combustion results indicate that as the pressure increases, NO emission decreases while N 2 O formation slightly increases. The pressurized pyrolysis/gasification results show that the release of NH 3 and HCN in CO 2 atmosphere significantly reduces with increasing pressure, while the other-N species are reduced to N 2 by char and CO at high pressure. NH 3 formation peaks at 700 °C while HCN emission increases significantly with increasing temperature. NH 3 yield is considerably higher than HCN yield when the temperature is below 800 °C. The correlation analysis shows that NO formation increases with the increase of the total amount of NH 3 and HCN released in the pyrolysis/gasification process. This study provides new insight into the evidence that the suppression of volatile-N under elevated pressure is one important reason for the decrease of NOx in the pressurized oxy-biomass combustion. [ABSTRACT FROM AUTHOR]

The deep and ultra-deep oil and gas has been a prominent exploration direction in the field of petroleum industry in recent years. The deep oil and gas resources are mainly distributed in the carbonate rocks, clastic rocks and igneous rocks, of which the carbonate rock reservoirs account for about 40% of global oil and gas reserves for their superior reservoir properties. Currently, a number of large oil and gas fields have been discovered in the deep marine carbonate rocks in China, especially in the Sichuan and Tarim Basin, thus showing a broad oil and gas exploration potential in the deep marine carbonate rocks. In this paper, the genesis and source of deep natural gas in the Tarim and Sichuan Basin has been systematically studied. The results show that the natural gas in the deep marine carbonate rock reservoirs is not only sourced from the deep-source rocks, but the substantial crack of crude oil in the reservoir under the condition of high burial depth and high geotemperature can provide abundant natural gas sources for the deep reservoir. Accordingly, the contribution of gas from oil cracking should be concerned in evaluation on deep natural gas resources. [ABSTRACT FROM AUTHOR]

Highlights: [•] The luminescence intensity of Mn2+ in ZnS:Mn,Eu is highly dependent on Eu2+. [•] The luminescence enhancement of Mn2+ by Eu2+ is as high as 5.5 times. [•] The X-ray luminescence enhancement is by a factor of 2.5. [•] There is energy transfer from Eu2+-related defects to Mn2+ in ZnS:Mn,Eu. [•] Energy transfer and phonon modification are responsible for the enhancement. [Copyright &y& Elsevier]

[Display omitted] • As 2 O 3 adsorption characteristics of mineral oxide sorbents at 300–900 °C were studied. • The order of As 2 O 3 adsorption at 300–700 °C is CaO > Fe 2 O 3 > Na 2 O > MgO > Al 2 O 3 > SiO 2. • The mechanism of As 2 O 3 adsorption was revealed by DFT analysis. As a highly toxic element of coal, arsenic (As) is mainly converted into As 2 O 3 vapor during coal combustion. Mineral oxides are effective and abundant sorbents to control As 2 O 3 emissions. In this paper, the characteristics of As 2 O 3 adsorption by mineral oxides were studied in a two-stage reactor, and the density of states, adsorption sites, and adsorption energies for the adsorption reaction were investigated using molecular simulation. The results demonstrate that CaO is an excellent As 2 O 3 sorbent. The As 2 O 3 adsorption effect of CaO, MgO, and Al 2 O 3 was found to become better with increasing temperature within the range of 300–900 °C. The order of As 2 O 3 adsorption at 300–700 °C follows CaO > Fe 2 O 3 > Na 2 O > MgO > Al 2 O 3 > SiO 2 , and SiO 2 hardly adsorbs any As 2 O 3. At 900 °C, the melting of Na 2 O and Fe 2 O 3 greatly reduces their As 2 O 3 adsorption capacity. The O atoms in Na 2 O/CaO/MgO/Al 2 O 3 /SiO 2 and the Fe atoms in Fe 2 O 3 are the adsorption active sites for As 2 O 3. The order of the calculated adsorption energy follows Fe 2 O 3 > Na 2 O > CaO > Al 2 O 3 > MgO > SiO 2 , and the As 2 O 3 adsorption involves chemical adsorption. The adsorption products are Ca 3 (AsO 4) 2 , FeAsO 4 , AlAsO 4 , etc., for which As exists in the form of As3+ and As5+, with As3+ transformed into As5+ with increasing adsorption temperature. [ABSTRACT FROM AUTHOR]

Mineral oxides are effective in-furnace sorbents used to control lead (Pb) emissions in flue gas at high temperatures. In this paper, the PbO/PbCl 2 adsorption characteristics of sorbents were investigated via experimental and density functional theory (DFT) methods. The results show that Si/Al-based compounds can chemically adsorb Pb, and the adsorption is related to the Si-O and Al-O bonds in the sorbents. Exposed Si and O atoms on SiO 2 surfaces and exposed Al and O atoms on Al 2 O 3 surfaces are the active sites for Pb adsorption, and PbO is easier to remove than PbCl 2. Pb adsorption is promoted in a mixture of SiO 2 and Al 2 O 3. Doping Si atoms into Al 2 O 3 (100) promotes PbO adsorption, and doped three-coordinate Si atoms have a more obvious promotion effect than doped two-coordinate Si atoms. Doping Al atoms into SiO 2 (001) has no obvious effect on PbO adsorption. The effect of temperature on Pb adsorption was studied by thermodynamic analysis. The Gibbs free energy difference for PbO adsorption on SiO 2 (001) increases from −373.04–32.42 kJ/mol as the temperature increases from 300 to 1800 K. High-temperature calcination changes the bond length and bond angle of the system, affecting the stabilities of atomic configurations and decreasing the Pb adsorption capacity. ga1 • The characteristics of Pb adsorption by mineral sorbents were analyzed. • The mechanism and thermodynamic of Pb adsorption were calculated. • High temperature calcination inhibits Pb adsorption by sorbents. • The mixture of SiO 2 and Al 2 O 3 has a promoting effect on Pb adsorption. [ABSTRACT FROM AUTHOR]

Fig. Schematic diagram of competing for active sites on the surface of sorbent particles. • Arsenic adsorption over mineral oxide sorbents in simulated flue gas was studied. • The preferred order of arsenic adsorption is CaO > MgO/Fe 2 O 3 > NaCl > Al 2 O 3 > SiO 2. • The effect mechanism of NaCl on the physical properties of sorbents was revealed. • Element distribution maps of the sorbents after arsenic adsorption was obtained. • The competition between acid gases and gas-phase arsenic over sorbents was clarified. Coal combustion is one of the major pathways by which arsenic enters the ecological environment. An effective method to control arsenic emissions in-furnace is to transform the arsenic from a vapour to fly ash particles using mineral sorbents. However, flue gas components have a significant effect on gas-phase arsenic adsorption, which limits the industrial application of mineral sorbents. In this paper, the effect mechanism of flue gas components (NaCl/HCl/SO 2 /CO 2) on gas-phase arsenic adsorption over different mineral oxide sorbents was investigated. The results demonstrate that the order of arsenic adsorption is CaO > MgO/Fe 2 O 3 > NaCl > Al 2 O 3 > SiO 2. NaCl promotes the arsenic adsorption of CaO above 800 °C, and the arsenic removal efficiency of CaO with 5 % NaCl is 52.51 % at 900 °C. NaCl inhibits the arsenic adsorption of MgO and Fe 2 O 3 , and promotes arsenic adsorption by Al 2 O 3 and SiO 2. Acid gases inhibit arsenic adsorption by the sorbents and the order of the inhibition intensity of acid gases at 700 °C is HCl > SO 2 > CO 2. The active sites (Ca O, FeO, or AlO bonds) in the sorbents are the main reaction sites for arsenic adsorption, and captured arsenic is in the form of AsO 2 1− and AsO 4 3-. [ABSTRACT FROM AUTHOR]

Coal combustion is one of the major pathways by which lead (Pb) enters the ecological environment. An effective method to control Pb emissions in a furnace is to transform the Pb from vapors to particles using Si-Al-based sorbents. However, the high price, poor thermal stability, and difficult molding of sorbents limits their application. Fly ash cenospheres (FACs) prepared from the waste of coal-fired power plants, which are mainly composed of SiO 2 and Al 2 O 3 , are ideal materials for Pb sorbents because of their high strength, light weight and low price. In this study, the adsorption and reaction mechanisms of FACs and several Si-Al-based sorbents for Pb vapors were investigated in a two-stage fixed-bed reaction system, and the thermal stability and regeneration characteristics of FACs were tested. The results indicate that the adsorption capacity for Pb vapors is FAC > kaolin > SiO 2 > γ-Al 2 O 3. The acidic sites, such as Si-O and Al-O bonds in FACs, were the main reaction sites for Pb adsorption and captured Pb in the form of stable Pb compounds (Pb2+). As the temperature increased from 700 to 1200 °C, the Pb adsorbed by FACs increased, and 55.21% of the Pb in the simulated flue gas was removed at 1200 °C. Kaolin is an excellent sorbent for Pb vapors. The adsorption capacity of kaolin for Pb first increases and then decreases with increasing temperature, and the maximum removal rate occurs at 1000 °C, reaching 33.46%. In addition, FACs are thermally stable and reusable. Therefore, the high-temperature application of FACs to remove Pb vapors has good prospects. [ABSTRACT FROM AUTHOR]

Currently, the severe fluctuation of steam temperature in double-reheat (DR) ultra-supercritical (USC) units has become a major problem that constrains their efficient and flexible operation, wherein the deviation of coal calorific value from the design value is one of the major reasons for this issue. However, the effect of coal calorific value variation on the steam temperature characteristics during the flexible operation of DR USC units remains unclear. A dynamic model of a 1000 MW DR USC unit is developed with primary principles and validated with real operation data. The effect of the coal calorific value variation on the steam temperature characteristics is revealed. Results show that as the calorific value of the coal increases, the main steam temperature can always maintain at the design value with attempering water adjustments, while the two reheat steam temperatures decrease. The steady-state deviations of the reheat steam temperatures are positively correlated with the magnitude of the coal calorific value variation, where the deviation of the secondary reheat steam temperature is larger. Meanwhile, as the load increases, the steady-state deviations of reheat steam temperatures increase, but the response time decreases. Finally, the effect of calorific value variation on the boiler efficiency is studied. As the coal calorific value increases, the boiler efficiency firstly rises caused by the decrease in the loss of the flue gas and then falls caused by the limited furnace temperature increase. This study provides guidance on the DR USC boiler operation under coal variation. • A dynamic model of a 1000 MW double-reheat ultra-supercritical unit is developed. • The effect of the coal calorific value variation on the steam temperature characteristics is revealed. • The effect of calorific value variation on the boiler efficiency is revealed. • This study provides guidance on the double-reheat ultra-supercritical boiler operation under coal variation. [ABSTRACT FROM AUTHOR]

The (001) surface of TiO 2 is proved to be more active than the (101) surface in the SCR reaction while the roles of these two surfaces were still unclear. The present study carefully compared the adsorption characteristics of the (001) and (101) surfaces of original and MnO 2 -loaded anatase by density functional theory calculations. The oxidizing ability and the feasibility of the oxygen vacancy formation were further explored. It was found that NH 3 , NO, NO 2 and O 2 tended to adsorb on the (001) surface rather than on the (101) surface and the (001) surface was more oxidizing and was more prone to generate oxygen vacancies. Loading MnO 2 had a significant promotion on the performance of the (001) surface. The adsorption performance of the Mn(001) surface was much better than that of the Mn(101) surface. The limiting reactions for N 2 and H 2 O production on the Mn(001) and Mn(101) surfaces were both the dissociation process of NH 3. The energy barriers of the SCR reaction on the Mn(001) surface were smaller than that on the Mn(101) surface, indicating that N 2 and H 2 O formation on the Mn(001) surface was easier. Unlabelled Image • NH 3 , NO, NO 2 and O 2 tended to adsorb on the (001) face rather than on the (101) face. • The (001) face was more oxidizing and was more prone to generate oxygen vacancies. • Loading MnO 2 had a great promotion on the performance of the (001) face. • The energy barrier of N 2 and H 2 O formation on the Mn(001) face was low. [ABSTRACT FROM AUTHOR]

Raman spectroscopy and several microstructure analysis techniques have been used to better characterize recently synthesized copper‐cysteamine Cu3Cl(SR)2, where R = CH2CH2NH2. Nanoparticles of this new copper‐cysteamine have been identified as having potential applications in radiation detection and cancer treatment because of the fact that they can be activated by light, X‐rays, ultrasound, and microwave radiation to produce reactive oxygen species. Three samples were grown under different conditions, and their microstructure was examined by using Raman spectroscopy, Fourier transform infrared, scanning electron microscopy, energy dispersive X‐ray scattering, and X‐ray diffraction. The Raman spectroscopy and Fourier transform infrared measurements identify numerous Raman active and infrared absorption bonds with wavenumbers ranging from 200 to 3,500 cm−1. Scanning electron microscopy scans show well‐faceted crystals varying in size from approximately 10 nm to 4 μm, energy dispersive X‐ray scattering measurements identify relative elemental composition (C = 48%, N = 37.5%, S = 5%, Cl = 2.6%, Cu = 7%), X‐ray diffraction data show the crystal plane spacing varies from 0.8454 to 0.8616 nm. The microstructure observed for the three samples is consistent with variations in the growth conditions. [ABSTRACT FROM AUTHOR]

Abstract Zn 1-x WO 4 :xLi+ (x = 0, 0.02, 0.05, 0.1) phosphors were synthesized by high-temperature solid-state method. The structural and luminescence properties of the samples were investigated through X-ray diffraction (XRD), scanning electron microscopy (SEM), Microconfocal Raman spectrometer(MR), Diffuse reflectance spectra (DRS) and Photoluminescence spectra. The Li-doped ZnWO 4 phosphors show photoluminescence with a broad band. Compared with the pure ZnWO 4 , the band gap of lithium doped samples shows a red shift measured by Diffuse reflectance spectra (DRS), which could be attributed to the doping effects. Moreover, photocatalytic activity test shows that the Li-doped ZnWO 4 phosphors exhibit higher catalytic activities than the pure ZnWO 4 for the degradation of Rhodamine B by the UV irradiation. The result shows that the Li-doped phosphors can enhance light harvest capability to generate more electron-hole pairs, and act as a trap center by decreasing the recombination of photogenerated electrons and holes. [ABSTRACT FROM AUTHOR]

Abstract Ti4+-doped ZnWO 4 phosphors were synthesized by a facile solid state reaction route. The structural and morphological features of the as-synthesized Ti4+-doped ZnWO 4 photocatalysts were intensively characterized by XRD(X-ray diffraction), XPS(X-ray photoelectron spectroscopy), UV–vis DRS(Ultraviolet-visible diffuse reflectance spectrum), PL(photoluminescence spectroscopy). The photocatalytic reaction tests have been decomposed by the solution of rhodamine B(RhB). The results showed that the Ti4+ -doped ZnWO 4 phosphors had a high photocatalytic activity, and RhB degradation rate of 97% within 120 min was achieved for the 0.01Ti4+-doped sample. The enhancement of photocatalytic performance for Ti4+-doped ZnWO 4 samples can be ascribed to reduce the recombination rate of photogenerated electron-hole pairs with the formation of new defects by Ti4+ doping. This study suggests that Ti4+-doped ZnWO 4 photocatalysts are promising for photocatalytic decomposition of organic contaminants. [ABSTRACT FROM AUTHOR]

A novel idea is proposed to improve the SO 2 tolerance of low-temperature selective catalytic reduction (SCR) catalysts by using a RHO zeolite membrane to separate NO from SO 2 to reduce the contact between SO 2 and the SCR catalysts. RHO zeolite membranes were prepared on a macroporous stainless steel tube. The results from XRD and SEM measurements indicated that the crystals on the surface were pure RHO zeolites and a uniform and continuous layer of RHO zeolite membrane covered the surface of the support. Permeation measurements using different feed gases indicated that the prepared RHO zeolite membrane could effectively separate NO from SO 2 . A maximum NO/SO 2 selectivity of 36.14 was obtained when using NO/SO 2 /N 2 mixtures. The SO 2 permeation decreased a lot in the present of water. Surface diffusion and activated diffusion were believed to be the main transport mechanisms of the RHO zeolite membrane. [ABSTRACT FROM AUTHOR]

Dy-Bi co-doped yttrium tungstate crystal materials were synthesized by high temperature solid-state method. To reveal the photoluminescence features and properties of the samples, some measurements have been taken. It turned out that different Bi concentrations play obvious influence in emission performance, and show visible light emission under ultraviolet light excitation. Besides, the effect of temperature on phase structure of samples has also been studied here. Superhigh X-ray luminescence of the phosphors exhibited the promising application in the field of high energy detection. The X-ray irradiation crystal resistance stability of the phosphors has also been investigated through the subsequent testing of XRD and spectra. [ABSTRACT FROM AUTHOR]

The burner tilt angle has a significant influence on the combustion characteristics of a furnace, but few studies have focused on this topic. In this study, a numerical model was developed and validated to investigate the effect of the burner tilt angle on the combustion and NO X emission characteristics of a 700 MWe pulverized-coal-fired boiler with deep-air-staging technology. The turbulence, heat transfer and chemical reactions in the furnace were reproduced in detail by the model. Deep insight into the effects of burner tilt angle on combustion and NO X emission characteristics was acquired. The results show that the turbulence intensity in the burnout zone of furnace increases as the burner tilt angle increases, leading to a significant increase in the reaction rate of CO combustion. Hence, the level of CO emission is continuously reduced. The char burnout rate changes little with increasing burner tilt angle since the kinetic reaction rate and oxygen diffusion rate increase while the particle residence time decreases. The NO X emission increases as the burner is tilted farther upward because of an enhancement in fuel NO formation and a decrease in NO reburning. This study provides useful guidelines for improving the performance of deep-air-staged tangentially coal-fired boilers. [ABSTRACT FROM AUTHOR]

Results of a systematic paleomagnetic study are reported based on Late Carboniferous to Early Permian sedimentary rocks on the north slope of the Tanggula Mountains, in the northern Qiangtang terrane (NQT), Tibet, China. Data revealed that magnetic minerals in limestone samples from the Zarigen Formation (CP^ z)are primarily composed of magnetite, while those in sandstone samples from the Nuoribagaribao Formation (P nr) are dominated by hematite alone, or hematite and magnetite in combination. Progressive thermal, or alternating field, demagnetization allowed us to isolate a stable high temperature component (HTC) in 127 specimens from 16 sites which successfully passed the conglomerate test, consistent with primary remnance. The tilt-corrected mean direction for Late Carboniferous to Early Permian rocks in the northern Qiangtang terrane is D =30.2°, I =- 40.9°, k =269.0, α =2.3°, N=16, which yields a corresponding paleomagnetic pole at 25.7°N, 241.5°E (d p/d m=2.8°/1.7°), and a paleolatitude of 23.4°S. Our results, together with previously reported paleomagnetic data, indicate that: (1) the NQT in Tibet, China, was located at a low latitude in the southern hemisphere, and may have belonged to the northern margin of Gondwana during the Late Carboniferous to Early Permian; (2) the Paleo-Tethys Ocean was large during the Late Carboniferous to Early Permian, and (3) the NQT subsequently moved rapidly northwards, perhaps related to the fact that the Paleo-Tethys Ocean was rapidly contracting from the Late Permian to Late Triassic while the Bangong Lake-Nujiang Ocean, the northern branch of the Neo-Tethys Ocean, expanded rapidly during this time. [ABSTRACT FROM AUTHOR]

Cerium doped Barium Fluoride (BaF 2 Ce) transparent ceramic was fabricated and its luminescence and scintillation properties were studied. The photoluminescence shows the emission peaks at 310 nm and 323 nm and is related to the 5d-4f transitions in Ce 3+ ion. Photo peak at 511 keV and 1274 keV were obtained with BaF 2 Ce transparent ceramic for Na-22 radioisotopes. Energy resolution of 13.5% at 662 keV is calculated for the BaF 2 Ce transparent ceramic. Light yield of 5100 photons/MeV was recorded for BaF 2 Ce(0.2%) ceramic and is comparable to its single crystal counterpart. Scintillation decay time measurements shows fast component of 58 ns and a relatively slow component of 434 ns under 662 keV gamma excitation. The slower component in BaF 2 Ce(0.2%) ceramic is about 200 ns faster than the STE emission in BaF 2 host and is associated with the dipole-dipole energy transfer from the host matrix to Ce 3+ luminescence center. [ABSTRACT FROM AUTHOR]

The Palogue Oilfield is the largest oilfield in the Melut Basin, an important petroliferous rift basin in Africa. Geochemical analyses, including gas chromatography and gas-mass chromatography were adopted to analyze the biomarker composition and geochemical characteristics of oils from the Palogue Oilfield and the neighboring Moleeta and Jamous lows. Oil-oil correlations were performed for the Palogue Oilfield and the Moleeta/Jamous lows, and the hydrocarbon accumulations of the Palogue Oilfield were studied based on the oil maturities, thermal evolution modelling of the Moleeta/Jamous lows and the petroleum system analysis of the Melut Basin. Geochemical analysis indicates that the oils of the Moleeta/Jamous lows are derived from terrestrial higher plants, with the low ratios (<1) of light n -alkanes to heavy n -alkanes (∑ n C 21- /∑ n C 22+) and the predominance of C 29 regular sterane, but there still are some geochemical differences in distribution shape of n -alkanes, paleoenvironments and maturities in these two lows. The oils of the Palogue Oilfield have mixed-source features and their geochemical characteristics are more like those of the Jamous low, and a few oils are like the oils in the Moleeta low. The Jamous low has a larger area and higher thermal maturity than the Moleeta low, and the abundant oils generated by the Al Renk source rocks (upper part of early Cretaceous) in the Jamous low are the primary contributors to the formation of the giant Palogue Oilfield. The vitrinite reflectance equivalent (Rc) converted by the methyl phenanthrene ratio indicates that the oil maturities of the Palogue Oilfield range from 0.65% to 1.07%. Thermal evolution modelling of the Moleeta/Jamous lows indicates that the Jamous low generated and expelled hydrocarbons earlier than the Moleeta low. The maturity of Al Renk source rocks reached 0.65% at 70Ma (Late Cretaceous) and 1.07% at 38Ma (Eocene) in the Jamous low, and reached 0.65% at 59Ma (Paleocene) and 1.07% at present in the Moleeta low. Thus, the high-maturity oils (R o > 1.07%) generated by the source rocks in the Jamous low since 38 Ma have not been discovered in the primary production layers of the Paleogene Samma and Yabus Formations in the higher part of the Palogue structure, a drape-anticline developing on a paleo-high between the Jamous and Moleeta lows. The maturity parameter of Ts/(Ts + Tm) shows that the oil maturities from late Cretaceous Formation in the well PS-7 and PS-8 are close to the oils in the Jamous Low and are significantly higher than the oils from the Paleogene Formation in the higher part of the Palogue structure. So, the Cretaceous Formation under the Paleogene pay zones and the Paleogene Formation in the lower part of the Palogue structure likely accumulated high-maturity oils from the Jamous low, which will enhance the exploration potential of the Palogue Oilfield. The petroleum system study indicates that the end of Oligocene (late Paleogene) is the critical moment for the Paleogene hydrocarbon accumulations in the Melut Basin. Whereas, the high-maturity oil accumulations (R o > 1.07%) in Cretaceous formations in the Palogue Oilfield occurred after 38Ma (late Eocene), when the Al Renk source rocks in the Jamous low started to enter the high thermal evolution stage with the R o > 1.07%. • The oils in the Moleeta and Jamous lows have different geochemical characteristics. • The Palogue Oilfield have mixed oil-source features. • The Jamous low generated and expelled hydrocarbons earlier than the Moleeta low. • High-maturity oils may develop in Cretaceous formations and lower part of Palogue structure. [ABSTRACT FROM AUTHOR]

J. Zhang, W. Chen, and co‐workers report non‐rare‐earth‐based white light phosphors composed of graphitic nitrogen carbon and copper‐cysteamine on page 6833. These composites exhibit a strong luminescence in the blue and red under ultraviolet single excitation, and are environmentally friendly, easy to synthesize, cost‐effective, and free of rare‐earth elements. These new white light phosphors have a good potential in solid lighting, displays, and crop improvement. [ABSTRACT FROM AUTHOR]

Human norovirus is a leading cause of acute gastroenteritis worldwide in a plethora of residential and commercial settings, including restaurants, schools, and hospitals. Methods for easily detecting the virus and for treating and preventing infection are critical to stopping norovirus outbreaks, and inactivation via nanoparticles (NPs) is a more universal and attractive alternative to other physical and chemical approaches. Using norovirus GI.1 (Norwalk) virus-like particles (VLPs) as a model viral system, this study characterized the antiviral activity of Au/CuS core/shell nanoparticles (NPs) against GI.1 VLPs for the rapid inactivation of HuNoV. Inactivation of VLPs (GI.1) by Au/CuS NPs evaluated using an absorbance-based ELISA indicated that treatment with 0.083 μM NPs for 10 min inactivated ~50% VLPs in a 0.37 μg/ml VLP solution and 0.83 μM NPs for 10 min completely inactivated the VLPs. Increasing nanoparticle concentration and/or VLP-NP contact time significantly increased the virucidal efficacy of Au/CuS NPs. Changes to the VLP particle morphology, size, and capsid protein were characterized using dynamic light scattering, transmission electron microscopy, and Western blot analysis. The strategy reported here provides the first reported proof-of-concept Au/CuS NPs-based virucide for rapidly inactivating human norovirus. [ABSTRACT FROM AUTHOR]

In the present paper, computational fluid dynamic modelings were established to research a newly presented re-heat steam temperature deviation solution on the basis of FLUENT 6.3.26 considering a 700 MWe tangentially fired pulverised-coal boiler, which confronted with severe flue gas and re-heat steam temperature deviation. The model was solidly validated by grid independence test and comparison with the experimental data obtained from a series of on-site measurements. Upon reliable validation, the model was further used to investigate the forming mechanism of re-heat steam temperature deviation as well as the influence of burner tilt angle on it. The conclusions mainly include (1) Residual swirling flow in the upper furnace caused the flue gas velocity and temperature deviations in crossover pass. For a typical anticlockwise tangential firing system, the flue gas velocity and temperature were lower in left part of crossover pass. The deviation of flue gas further generated the convective heat transfer imbalance of final re-heater, therefore, the temperature deviation of re-heat steam was severe. (2) Tilting the burner upward can effectively reduce the intensity of residual flow as well as the flue gas deviation degree. The + 11° tilt angle of burner was relatively optimum considering the flue gas deviation and final re-heater overheating potential. Specifically, the intensity of residual swirl flow dropped 44% with burner tilting upward for + 11°. Practical operation of boiler demonstrated that the reheat steam temperature deviation was reduced from 22 °C to 10 °C in this case. (3) When the tilt angle of additional air (AA) was bias set, the flow field of upper furnace was changed. Consequently, the residual swirl flow intensity and the flue gas deviation were reduced considerably. On-site measurements indicated that the combination of tilting burner upward for + 11° and setting the bias of AA tilt angle for 10° can further reduce the re-heat steam temperature deviation to 4 °C. [ABSTRACT FROM AUTHOR]

We report paleomagnetic results from the Late Carboniferous-Late Permian strata in eastern Tibet (China), and aim to clarify the tectonic and paleogeographic evolution of the northern Qiangtang-Qamdo block, which is the key to the study of plate boundary between the Gondwanaland and the Eurasia during the late Paleozoic. Two hundred and nineteen samples-including limestone, muddy siltstone, basalt, lava, and tuff-were collected at 24 sites in the Upper Carboniferous and Middle-Upper Permian successions. A systematic study of rock magnetism and paleomagnetism yields three reliable paleomagnetic pole positions. Both hematite and magnetite occurred in the Late Carboniferous limestone samples. The demagnetization curve shows a characteristic double-component, with the remanent magnetization (ChRM) exhibiting a positive polarity (negative inclination). In the Late Permian limestone, tuff, and basalt, magnetic information were recorded primarily in magnetite, although a small fraction of them was found in hematite in basalt. The demagnetization curve illustrates a double or single component, with the ChRM showing a negative polarity (positive inclination), which has passed the classic fold test successfully. The single polarity features of the ChRM directions of the Late Carboniferous and Middle-Late Permian rocks are respectively related to the Kiaman positive and reversed polarities under the stratigraphic coordinates. This, in turn, indicates that both ChRMs directions represent the original remanence directions. By comparison with the previously published paleomagnetic results from the late Paleozoic rocks in the northern Qiangtang Range, we suggest that: (1) Qamdo and northern Qiangtang block were independent of each other during the Late Carboniferous to the Early Permian periods. The north Lancangjiang ocean basin between the two blocks may have closed before the Middle Permian and been involved in the continent-continent collision stage in the Late Permian-Early Triassic periods. (2) The northern Qiangtang-Qamdo Block paleogeographically was situated at low to intermediate latitudes in the Southern Hemisphere in the Late Carboniferous-Late Permian periods, and began to displace northward in the Early Triassic, with an amount of more than 5000 km northward transport from its current location. [ABSTRACT FROM AUTHOR]